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        <div class="max-w-6xl mx-auto">
            <div class="flex flex-col md:flex-row items-center">
                <div class="md:w-1/2 mb-10 md:mb-0">
                    <h1 class="text-4xl md:text-5xl font-bold mb-4 leading-tight font-serif">RocketMQ流量控制机制</h1>
                    <p class="text-xl opacity-90 mb-8">全链路消息流量控制的艺术与科学</p>
                    <div class="flex space-x-4">
                        <span class="bg-white bg-opacity-20 px-4 py-2 rounded-full text-sm font-medium">分布式消息队列</span>
                        <span class="bg-white bg-opacity-20 px-4 py-2 rounded-full text-sm font-medium">高并发系统</span>
                        <span class="bg-white bg-opacity-20 px-4 py-2 rounded-full text-sm font-medium">系统稳定性</span>
                    </div>
                </div>
                <div class="md:w-1/2">
                    <div class="mermaid">
                        flowchart TD
                            A[Producer] -->|发送消息| B(Broker)
                            B -->|推送消息| C[Consumer]
                            A --> D[客户端限流]
                            A --> E[批量发送]
                            C --> F[消费线程控制]
                            C --> G[批量消费]
                            B --> H[写入限流]
                            B --> I[读取限流]
                            D --> J[线程池控制]
                            D --> K[发送超时]
                            F --> L[线程数设置]
                            G --> M[批量大小]
                            H --> N[内存流控]
                            H --> O[磁盘流控]
                            I --> P[拉取控制]
                    </div>
                </div>
            </div>
        </div>
    </div>

    <!-- Main Content -->
    <div class="max-w-6xl mx-auto px-6 py-12">
        <!-- Introduction -->
        <div class="bg-white rounded-xl p-8 mb-12 section-card">
            <div class="flex items-center mb-6">
                <i class="fas fa-info-circle text-3xl text-blue-500 mr-4"></i>
                <h2 class="text-2xl font-bold font-serif">流量控制的重要性</h2>
            </div>
            <p class="text-lg text-gray-700 mb-4">在分布式消息系统中，流量控制是确保系统稳定性的关键机制。RocketMQ作为一个高性能、高可用的消息中间件，提供了从Producer到Broker再到Consumer的全链路流量控制方案。</p>
            <p class="text-lg text-gray-700">合理的流量控制可以防止系统过载，平衡生产与消费速率，保障系统在高并发场景下的稳定性与可靠性。</p>
        </div>

        <!-- Producer Section -->
        <div class="mb-16">
            <div class="flex items-center mb-8">
                <div class="h-1 bg-blue-500 flex-1"></div>
                <h2 class="text-3xl font-bold mx-6 font-serif">Producer端流量控制机制</h2>
                <div class="h-1 bg-blue-500 flex-1"></div>
            </div>

            <div class="grid md:grid-cols-2 gap-8">
                <!-- 发送消息限流 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-tachometer-alt text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">发送消息限流</h3>
                    </div>
                    <p class="text-gray-700 mb-4">RocketMQ在Producer端提供了多种流量控制机制来控制消息发送速率。</p>
                    
                    <div class="mb-4">
                        <h4 class="font-medium text-lg mb-2 flex items-center">
                            <i class="fas fa-laptop-code text-blue-400 mr-2"></i>
                            客户端限流
                        </h4>
                        <ul class="list-disc pl-5 space-y-1 text-gray-700">
                            <li><span class="font-medium">线程池控制</span>: 通过<code>setAsyncSenderExecutor</code>自定义线程池</li>
                            <li><span class="font-medium">批量发送</span>: 减少网络交互次数，提高吞吐量</li>
                            <li><span class="font-medium">发送超时</span>: 设置<code>sendMsgTimeout</code>控制超时时间</li>
                        </ul>
                    </div>
                    
                    <div class="code-block rounded-lg p-4 mb-4 overflow-x-auto">
                        <pre class="text-sm"><code>DefaultMQProducer producer = new DefaultMQProducer("ProducerGroupName");
// 设置发送消息超时时间为5秒
producer.setSendMsgTimeout(5000);
// 设置异步发送线程池
producer.setAsyncSenderExecutor(customExecutorService);</code></pre>
                    </div>
                    
                    <div>
                        <h4 class="font-medium text-lg mb-2 flex items-center">
                            <i class="fas fa-expand-arrows-alt text-blue-400 mr-2"></i>
                            限制单次发送消息大小
                        </h4>
                        <p class="text-gray-700 mb-2">默认限制单条消息最大长度为4MB，可通过Broker配置调整:</p>
                        <div class="code-block rounded-lg p-4 overflow-x-auto">
                            <pre class="text-sm"><code># 默认为4MB
maxMessageSize=4194304</code></pre>
                        </div>
                    </div>
                </div>

                <!-- 流控与背压机制 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-compress-arrows-alt text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">流控与背压机制</h3>
                    </div>
                    <p class="text-gray-700 mb-4">RocketMQ实现了完善的流控与背压机制来应对系统压力。</p>
                    
                    <div class="space-y-4">
                        <div class="p-4 bg-blue-50 rounded-lg">
                            <h4 class="font-medium flex items-center">
                                <i class="fas fa-exchange-alt text-blue-400 mr-2"></i>
                                RemotingCommand流控
                            </h4>
                            <p class="text-gray-700 mt-1">当Producer发送请求过快时，Broker会返回流控响应码，Producer收到后会进行退避重试。</p>
                        </div>
                        
                        <div class="p-4 bg-blue-50 rounded-lg">
                            <h4 class="font-medium flex items-center">
                                <i class="fas fa-random text-blue-400 mr-2"></i>
                                发送队列选择机制
                            </h4>
                            <p class="text-gray-700 mt-1">当某个Broker负载过高时，Producer会自动选择其他队列发送消息，实现负载均衡。</p>
                        </div>
                        
                        <div class="p-4 bg-blue-50 rounded-lg">
                            <h4 class="font-medium flex items-center">
                                <i class="fas fa-shield-alt text-blue-400 mr-2"></i>
                                故障规避
                            </h4>
                            <p class="text-gray-700 mt-1">当Broker响应时间过长或失败率高时，Producer会暂时将其加入规避列表，减少向其发送消息。</p>
                        </div>
                    </div>
                </div>
            </div>
        </div>

        <!-- Consumer Section -->
        <div class="mb-16">
            <div class="flex items-center mb-8">
                <div class="h-1 bg-blue-500 flex-1"></div>
                <h2 class="text-3xl font-bold mx-6 font-serif">Consumer端消费限流的方法</h2>
                <div class="h-1 bg-blue-500 flex-1"></div>
            </div>

            <div class="grid md:grid-cols-2 gap-8">
                <!-- 并发消费控制 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-users text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">并发消费控制</h3>
                    </div>
                    <p class="text-gray-700 mb-4">通过控制消费线程数来调节消费能力。</p>
                    
                    <div class="code-block rounded-lg p-4 mb-4 overflow-x-auto">
                        <pre class="text-sm"><code>DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("ConsumerGroupName");
// 设置消费线程数，默认为20
consumer.setConsumeThreadMin(10);
consumer.setConsumeThreadMax(30);</code></pre>
                    </div>
                    
                    <div class="p-4 bg-blue-50 rounded-lg">
                        <h4 class="font-medium flex items-center">
                            <i class="fas fa-cog text-blue-400 mr-2"></i>
                            配置建议
                        </h4>
                        <p class="text-gray-700 mt-1">根据机器CPU核心数和业务处理复杂度设置合理的线程数，过高会导致上下文切换开销，过低则无法充分利用资源。</p>
                    </div>
                </div>

                <!-- 消费速率控制 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-tachometer-alt text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">消费速率控制</h3>
                    </div>
                    
                    <div class="mb-4">
                        <h4 class="font-medium text-lg mb-2 flex items-center">
                            <i class="fas fa-boxes text-blue-400 mr-2"></i>
                            批量消费设置
                        </h4>
                        <div class="code-block rounded-lg p-4 overflow-x-auto">
                            <pre class="text-sm"><code>// 设置一次消费消息的条数，默认为1
consumer.setConsumeMessageBatchMaxSize(10);</code></pre>
                        </div>
                    </div>
                    
                    <div class="mb-4">
                        <h4 class="font-medium text-lg mb-2 flex items-center">
                            <i class="fas fa-clock text-blue-400 mr-2"></i>
                            消费频率控制
                        </h4>
                        <div class="code-block rounded-lg p-4 overflow-x-auto">
                            <pre class="text-sm"><code>// 消费线程每隔1000ms才进行一次消费
consumer.setPullInterval(1000);</code></pre>
                        </div>
                    </div>
                </div>

                <!-- 流控阈值与手动ACK -->
                <div class="md:col-span-2">
                    <div class="grid md:grid-cols-2 gap-8">
                        <!-- 流控阈值设置 -->
                        <div class="bg-white rounded-xl p-6 section-card">
                            <div class="flex items-center mb-4">
                                <i class="fas fa-sliders-h text-2xl text-blue-500 mr-3"></i>
                                <h3 class="text-xl font-bold">流控阈值设置</h3>
                            </div>
                            
                            <div class="code-block rounded-lg p-4 mb-4 overflow-x-auto">
                                <pre class="text-sm"><code>// 设置消费者流控阈值，当消息堆积数超过阈值时触发流控
consumer.setPullThresholdForQueue(1000);
// 设置基于消息大小的流控阈值
consumer.setPullThresholdSizeForQueue(100 * 1024 * 1024);</code></pre>
                            </div>
                            
                            <p class="text-gray-700">RocketMQ 4.x版本引入了基于消费进度的流控机制，可以防止消息堆积过多导致系统压力过大。</p>
                        </div>

                        <!-- 手动ACK控制 -->
                        <div class="bg-white rounded-xl p-6 section-card">
                            <div class="flex items-center mb-4">
                                <i class="fas fa-hand-paper text-2xl text-blue-500 mr-3"></i>
                                <h3 class="text-xl font-bold">手动ACK控制</h3>
                            </div>
                            
                            <div class="code-block rounded-lg p-4 overflow-x-auto">
                                <pre class="text-sm"><code>consumer.setMessageListener(new MessageListenerConcurrently() {
    @Override
    public ConsumeConcurrentlyStatus consumeMessage(List&lt;MessageExt&gt; msgs, ConsumeConcurrentlyContext context) {
        // 处理消息
        // ...
        
        // 根据业务处理能力返回不同状态
        if (canProcessNow()) {
            return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
        } else {
            // 稍后重试，实现流控
            return ConsumeConcurrentlyStatus.RECONSUME_LATER;
        }
    }
});</code></pre>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>

        <!-- Broker Section -->
        <div class="mb-16">
            <div class="flex items-center mb-8">
                <div class="h-1 bg-blue-500 flex-1"></div>
                <h2 class="text-3xl font-bold mx-6 font-serif">Broker端的流量控制策略</h2>
                <div class="h-1 bg-blue-500 flex-1"></div>
            </div>

            <div class="grid md:grid-cols-2 gap-8">
                <!-- 写入限流机制 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-download text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">写入限流机制</h3>
                    </div>
                    
                    <div class="mb-4">
                        <h4 class="font-medium text-lg mb-2 flex items-center">
                            <i class="fas fa-file-upload text-blue-400 mr-2"></i>
                            CommitLog写入流控
                        </h4>
                        <div class="code-block rounded-lg p-4 overflow-x-auto">
                            <pre class="text-sm"><code># 是否开启流控
enableFlowControl=true
# 流控阈值，默认100MB
flowControlThreshold=104857600
# 流控持续时间，单位毫秒
flowControlWaterMark=200</code></pre>
                        </div>
                    </div>
                    
                    <div class="p-4 bg-blue-50 rounded-lg">
                        <h4 class="font-medium flex items-center">
                            <i class="fas fa-server text-blue-400 mr-2"></i>
                            发送消息流控
                        </h4>
                        <ul class="list-disc pl-5 mt-1 space-y-1 text-gray-700">
                            <li><span class="font-medium">内存占用流控</span>: 当内存使用率超过阈值时拒绝写入</li>
                            <li><span class="font-medium">磁盘使用率流控</span>: 当磁盘使用率超过阈值时拒绝写入</li>
                        </ul>
                        
                        <div class="code-block rounded-lg p-4 mt-2 overflow-x-auto">
                            <pre class="text-sm"><code># 内存占用流控阈值，默认75%
memoryLimitRatio=75
# 磁盘占用流控阈值，默认90%
diskSpaceWarningLevelRatio=90</code></pre>
                        </div>
                    </div>
                </div>

                <!-- 读取限流机制 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-upload text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">读取限流机制</h3>
                    </div>
                    
                    <div class="mb-4">
                        <h4 class="font-medium text-lg mb-2 flex items-center">
                            <i class="fas fa-box-open text-blue-400 mr-2"></i>
                            拉取消息流控
                        </h4>
                        <div class="code-block rounded-lg p-4 overflow-x-auto">
                            <pre class="text-sm"><code># 单次拉取最大消息数，默认32条
pullBatchSize=32
# 单次拉取最大消息大小，默认32MB
pullMessageMaxBytes=33554432</code></pre>
                        </div>
                    </div>
                    
                    <div class="mb-4">
                        <h4 class="font-medium text-lg mb-2 flex items-center">
                            <i class="fas fa-network-wired text-blue-400 mr-2"></i>
                            网络流量控制
                        </h4>
                        <div class="code-block rounded-lg p-4 overflow-x-auto">
                            <pre class="text-sm"><code># 写入流量控制，单位字节/秒
flowControlWriteQps=100000000
# 读取流量控制，单位字节/秒
flowControlReadQps=100000000</code></pre>
                        </div>
                    </div>
                    
                    <div class="p-4 bg-blue-50 rounded-lg">
                        <h4 class="font-medium flex items-center">
                            <i class="fas fa-crown text-blue-400 mr-2"></i>
                            商业版特有功能
                        </h4>
                        <ul class="list-disc pl-5 mt-1 space-y-1 text-gray-700">
                            <li><span class="font-medium">基于Topic的流控</span>: 不同Topic设置不同策略</li>
                            <li><span class="font-medium">时间窗口流控</span>: 限时限制发送量</li>
                            <li><span class="font-medium">动态流控</span>: 根据负载动态调整阈值</li>
                        </ul>
                    </div>
                </div>
            </div>
        </div>

        <!-- Practice Section -->
        <div>
            <div class="flex items-center mb-8">
                <div class="h-1 bg-blue-500 flex-1"></div>
                <h2 class="text-3xl font-bold mx-6 font-serif">实践建议</h2>
                <div class="h-1 bg-blue-500 flex-1"></div>
            </div>

            <div class="grid md:grid-cols-3 gap-8">
                <!-- 生产环境配置 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-cogs text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">生产环境配置</h3>
                    </div>
                    
                    <div class="space-y-4">
                        <div class="p-3 bg-blue-50 rounded-lg">
                            <h4 class="font-medium flex items-center">
                                <i class="fas fa-rocket text-blue-400 mr-2"></i>
                                Producer端
                            </h4>
                            <p class="text-gray-700 mt-1 text-sm">根据业务峰值设置合理的线程池大小和超时时间</p>
                        </div>
                        
                        <div class="p-3 bg-blue-50 rounded-lg">
                            <h4 class="font-medium flex items-center">
                                <i class="fas fa-users-cog text-blue-400 mr-2"></i>
                                Consumer端
                            </h4>
                            <p class="text-gray-700 mt-1 text-sm">根据消息处理能力设置合理的消费线程数和批量消费大小</p>
                        </div>
                        
                        <div class="p-3 bg-blue-50 rounded-lg">
                            <h4 class="font-medium flex items-center">
                                <i class="fas fa-server text-blue-400 mr-2"></i>
                                Broker端
                            </h4>
                            <p class="text-gray-700 mt-1 text-sm">根据硬件资源设置合理的流控阈值，避免系统过载</p>
                        </div>
                    </div>
                </div>

                <!-- 监控与告警 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-chart-line text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">监控与告警</h3>
                    </div>
                    
                    <div class="space-y-3">
                        <div class="flex items-start">
                            <div class="bg-blue-100 p-2 rounded-full mr-3">
                                <i class="fas fa-bell text-blue-500"></i>
                            </div>
                            <div>
                                <h4 class="font-medium">关键指标监控</h4>
                                <ul class="list-disc pl-5 text-sm text-gray-700">
                                    <li>消息发送TPS和RT</li>
                                    <li>消息消费TPS和RT</li>
                                    <li>消息堆积量</li>
                                    <li>Broker资源使用率</li>
                                </ul>
                            </div>
                        </div>
                        
                        <div class="flex items-start mt-4">
                            <div class="bg-blue-100 p-2 rounded-full mr-3">
                                <i class="fas fa-exclamation-triangle text-blue-500"></i>
                            </div>
                            <div>
                                <h4 class="font-medium">告警策略</h4>
                                <p class="text-sm text-gray-700">当关键指标超过阈值时，及时触发告警并采取措施避免系统过载</p>
                            </div>
                        </div>
                    </div>
                </div>

                <!-- 流控策略调优 -->
                <div class="bg-white rounded-xl p-6 section-card">
                    <div class="flex items-center mb-4">
                        <i class="fas fa-tools text-2xl text-blue-500 mr-3"></i>
                        <h3 class="text-xl font-bold">流控策略调优</h3>
                    </div>
                    
                    <div class="space-y-4">
                        <div class="flex items-start">
                            <div class="bg-blue-100 p-2 rounded-full mr-3">
                                <i class="fas fa-chart-bar text-blue-500"></i>
                            </div>
                            <div>
                                <h4 class="font-medium">业务周期调整</h4>
                                <p class="text-sm text-gray-700">根据业务高低峰期动态调整流控限制，提高资源利用率</p>
                            </div>
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                            <div>
                                <h4 class="font-medium">压力测试</h4>
                                <p class="text-sm text-gray-700">通过压测找到最佳流控参数配置，平衡性能与稳定性</p>
                            </div>
                        </div>
                        
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                            <div class="bg-blue-100 p-2 rounded-full mr-3">
                                <i class="fas fa-sync-alt text-blue-500"></i>
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                                <h4 class="font-medium">持续优化</h4>
                                <p class="text-sm text-gray-700">随业务变化和系统升级不断优化流控策略</p>
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